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OLED Displays Technology Primer and Forecasting

HawKe writes "OLEDs are back in the news and Audioholics reports on what makes the technology so special as well as who leads the pack in currently shipping products, vaporware, and displays that are on the horizon. The crux of the matter is whether or not OLEDs, the "eco-friendly" choice, can outpace current LCD and plasma display advances. In order to enter and dominate the home theater and computer display markets, they must not only establish themselves, but also beat the leaders in price and performance."

25 of 197 comments (clear)

  1. Expensive. by RucasRiot · · Score: 0, Informative

    By principle these are going to be very costly and difficult to manufacture, I really don't see the price going down very soon. That being said, this is a very promising technology, and it may just be what is needed to get people (like me) to switch from CRTs (once the price goes down, of course)

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    1. Re:Expensive. by ajlitt · · Score: 5, Informative

      RTFA. The article's main point is that OLED manufacturing processes, once some of the technological hurdles are overcome, is far, far cheaper than TFT or plasma. The contender for assembly methodology is to use an inkjet-like system to print the OLED polymers onto the substrate and use common metal sputtering techniques for the interconnects. They even mentioned that a key price advantage is the ability to integrate driving circuitry onto the same substrate as the display, saving the cost of having to use off-screen drivers (this is also being used in newer CG-TFT displays).

    2. Re:Expensive. by Jeff+DeMaagd · · Score: 3, Informative

      It isn't just a manufacturing hurdle. IMO, The articles (er, press releases) completely ignores the most significant drawback: that the different colors fade at different speeds.

  2. 1000 hours? by cbiffle · · Score: 4, Informative

    I own one of the Pioneer decks they reference in the article. Its display is positively stunning, though I wish I'd waited a couple years for the color ones that can play MPEG off of the CD. Mmm.

    In the article, though, they list among OLED's advantages "1000 hour life."

    That's 41 and two-thirds days. This is clearly wrong; my stereo's been going strong for nearly two years.

    Just FYI.

    1. Re:1000 hours? by SharpFang · · Score: 3, Informative

      5h a day, 200 days in a year, that's 2 years. Plus the problem is about the color ones. B&W may get fuzzy at worst. In color ones, colors mix. The display will work much longer than 1000 hours, but the colors will be a bad mess.

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    2. Re:1000 hours? by MBAFK · · Score: 4, Informative

      Couple of doctors thoughts
      Snipped from that page:
      ...Right now, OLED displays are commercially available in cell phones and car radios with lifetimes over 10,000 hours...

    3. Re:1000 hours? by El+Puerco+Loco · · Score: 4, Informative

      I think that is a misprint, current displays have a lifespan of ~10,000, and that is currently limited by the blue LEDs, the red and green last ~20,000 hours, so after 10,000 the color balance starts to degrade pretty rapidly. BTW Seiko Epson recently unveiled a 40 inch OLED display. So this is definitely something that is feaseable now.

  3. Re:Great News... by SharpFang · · Score: 5, Informative

    Except the worst pain about OLEDs nowadays is that they burn out (or more like diffuse and get blurry) way faster than anything else - that's the barrier that keeps them from entering the market.

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  4. Black levels, refresh rate: what?! by NSash · · Score: 2, Informative

    Some of the challenges OLEDs have to face:
    * Ensuring competitive refresh rates, contrast ratios, black levels and overall performance


    Why on earth would black levels be an issue for an LED display? I thought that was a problem unique to LCDs, due to their backlighting. Furthermore, I was under the impression that refresh rates for today's LED displays already surpass LCDs; that high refresh rates are a feature of the technology. Is the reporter full of it, or am I misunderstanding something?

    1. Re:Black levels, refresh rate: what?! by poptones · · Score: 2, Informative
      organic leds are not exactly like silicon leds. They are apparently quite a bit more capacitive than the "conventional" LEDs you are likely thinking of ( which would be expected since they are, after all, made from plastic - a material used to make capacitor dielectrics). this capacitance will either slow down refresh cycles or drive up power consumption. In a home unit you could probably live with the added power consumption to get a great display, in a notebook that might be a bit more of an issue.

      But even if you can live with higher power dissipation, that power has to "dissipate" somewhere. On a glass display, the only place that power could go is through the glass itelf or maybe on a heatsink across the back.

      It seems certain this technology will become inexpensive enough to compete. I just wish they would hurry up about it...

    2. Re:Black levels, refresh rate: what?! by UserChrisCanter4 · · Score: 3, Informative

      For the same reason that self-illuminating plasma displays have a weak black level: the amount of light they can put behind those colors. The darker the glass is, the brighter a color has to be to penetrate that black and still look decent, hence the reason a lot of plasmas have a "smoke" black. OLEDs will need to be much brighter to penetrate a true black, and balancing that brightness with MTBF will indeed be a challenge.

      Of coursre, all other things being equal, I'll be perfectly happy to forego the heavy power usage of LCDs and the ludicrous power usage of plasma displays.

    3. Re:Black levels, refresh rate: what?! by UserChrisCanter4 · · Score: 2, Informative

      To my understanding (I don't claim to be an expert), plasma doesn't work that way. Two levels of glass are used to seal in a cell of gas, which when charged produces a colored light. It isn't backlit, but rather produces its own light along with the color (presumably three color layers to produce the gamut it needs to). It's really nothing more than a stop-gap technology, though, because LCDs couldn't be fabbed in the sizes plasmas could be produced in.

      Now comes the peculiar point. It would seem to me that you could simply have a black background, with the plasma cells above it turned off, and it would produce a perfect black, but it doesn't work that way. For whatever reason, the black is closer to the front of the screen, similar to the way a CRT is layed out. Again, I don't have a full knowledge of the intricate workings of the technology, or the reasons why its laid out that way (perhaps it simply looks weird to have the black at the back), and thus the colors have to penetrate the black to be seen. Because plasmas can't produce as bright a colors as a CRT, their blacks can't be as dark. If an OLED had to abide by similar visual restrictions, such as would be the case if blacks at the back looked strange, then we'd be back to sqaure one.

    4. Re:Black levels, refresh rate: what?! by Anonymous Coward · · Score: 1, Informative

      A display can only be as black as the material it is made of. The dark gray of an unpowered CRT is the darkest color it can display. You just don't notice it because the colors are so bright in relation. One common workaround is to surround the pixels with a black grid that serves to darken the non-glowing parts of the screen.

      If OLEDs are naturally gray, then they won't be able to show any colors darker than that.

      LCDs, of course, have it even worse. In addition to the gray of the screen, the background is very bright, and an off pixel is nowhere near 100% effective at blocking the light pouring through it from behind.

  5. Re:Is Organic LED == degradable? by Anonymous Coward · · Score: 1, Informative

    As clearly stated in the easy to read ARTICLE: ~1000 hours.

  6. Re:Great News... by Anonymous Coward · · Score: 5, Informative

    Brighter than? LCDs have no brightness, its all from a backlight. OLEDs emit light, thats why you can have paper thin OLEDs.. and without the viewing angle problems caused by backlights and their distance from the screen and how they emit light

  7. Same thing with plasma tvs by ad0gg · · Score: 3, Informative

    Plasma tvs have about 20,000 hours life. Something to think about when you buy an open box plasma tv from bestbuy or circuit city since its probably been on 14+ hours a day for 6 months or longer. So you'll get about 5 years of life out of it, instead of 10 to 14 years with a new one. I'm amazed that plasma tvs are so common now a days, I see them used as billboards at theaters and malls. These things are on 24 hours a day that means 2 years later they'll need to be replaced.

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  8. Re:Is Organic LED == degradable? by ad0gg · · Score: 4, Informative
    OLED Life is 1000 hours
    LCD life is 45,000 hours
    Plasma life is 14,000 hours
    CRT life is 45,000 hours

    I'll stick with LCD or CRT until plasma or OLED become cheap enough that replacing them is like replacing the brake pads on your car.

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    Have you ever been to a turkish prison?

  9. Re:Can it 'display' black? by mr_zorg · · Score: 4, Informative

    Yes, you're absolutely right. Since the pixels in OLED are light-emitting they can display true black by simply turning off -- just light in a CRT display. The reason LCD can't display true black is because they have to block the backlight to render black, and they're just not 100% light blocking...

  10. CCFT backlight by Powercntrl · · Score: 5, Informative

    LCD life is 45,000 hours

    That's really just due to the fact that eventually the CCFT backlight will croak. With most LCD displays, it's just a $15-$25 part and your LCD is back in business. If you factor in CCFT replacement, an LCD monitor should last as long as the controller circuitry keeps functioning - most likely, a LONG ASS TIME.

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  11. two things... by poptones · · Score: 4, Informative
    a) where do you find an LCD panel rated at 45,000 hrs? I've never even seen a backlight ccfl rated at that, much less an lcd panel.

    b) lifecycle numbers are under bias. FWIW many electrolytic capacitors are also rated for 1000 hr lifecycles, and you don't see many tv sets just blowing up after 6 months. "Lifetime" typically means "this much time until specifications change X%." For capacitors it's typically a 20% change in value, and this change is not linear - the greatest change comes in the first 100 hrs or so and degrades slower after that.

    Given "normal" program material and use in a true color display "1000 hrs" absolutely does NOT mean "it dies in 40 days." It means after 1000 hrs under bias any given pixel element will lose 50% of its brightness. In a 1/64 duty cycle system this means you can multiply those 40 days by 64 - about 2500 days, or 7 years.

    As someone else has pointed out, the real challenge is getting a reliable means of producing panels with consistent degradation of all pixels over time. If you have 10% of the red oleds fading after 800 hrs and 20% of the green elements fading after 1200 hrs you're going to have a display with splotches of color that, over years, becomes worse and worse.

    Still, this is no worse than LCDs that typically require repair after just a couple of years because their backlight (or the inverter driving it) has failed. At best you can hope for a warning as the color gradually turns pink - or maybe you just turn it on one day and find the screen is "dead." Or your projection set - those bulbs are often a couple hundred bucks, and damn few are rated at more than 2000 hrs lifetime. Given all that, this 1000hrs don't seem bad at all.

  12. Re:Same thing with plasma tvs - Wrong by bentradio · · Score: 2, Informative

    I am sick of this FUD. Please, if you are going to post things about plasmas, at least be accurate. Of the larger plasma makers, most like Panasonic or Pioneer are currently at 60,000 hours until phosphor half-brightness, and the majority of the rest are at 30,000. 20,000 hours was right in 2002, when those stats were published, but just as in computers, things move fast. If I were to quote the state of Linux in 2002 as the current state, I am sure I'd get flamed mightily.

    Sorry if I came out as mad at you, I'm not, but there was another post here which claimed 10,000 hours as the current life span, and I just want to set the record straight.

    BTW I do not own a plasma, I own a Sony XBR CRT.

  13. Laws of color mixing suspended by michaelmalak · · Score: 5, Informative
    From the article:
    ... pixels of red, green, and blue material are applied.

    [...] All colors of the visible spectrum are available

    Somehow, I don't think so.
  14. Re:OLED not yet for home theater monitors. by Cecil · · Score: 2, Informative

    screen burn issue that plagues CRT

    Have you been living in the wonderful world of 20 years ago? CRT monitor burn-in is almost nonexistant for any modern, decent-quality monitor. You would have to try very hard to get a monitor to burn in these days.

    Rear-projection CRT I don't have any experience with. I hear that yes, burn-in can be a problem with those, probably due to the brightness they need to achieve to project that image onto the screen. But they only comprise a minority of CRTs, and to lump all CRTs in there as having a burn-in problem is a bit unfair, I think.

    Admittedly CRTs don't last as long as they used to, I guess because of the precision they require to accomplish things we take for granted like variable refresh rates, variable resolution, and 0.22 dot pitch. Monochrome 40x25 isn't that hard to do legibly. But they still have a longer useful lifetime than any of the competing display technologies. Which isn't to say they're the best. They're big, HEAVY, power-guzzling monsters, and I'd love to have an OLED display myself.

    If I can use OLED displays for my photographic work, rock on. I look forward to it. Until then, I shall put up with my 21" beta-radiation-box. Oh, and as long as I'm making photographer wishes, I hope they give me some cheap white OLEDs for household lights too. All this 3200K tungsten light makes my camera sad. ;)

  15. Re:The TV could kill!! by tarunthegreat2 · · Score: 4, Informative

    I was about to contradict you...until I googled and saw This

  16. OLED - small molecule or polymer by flend · · Score: 4, Informative

    There seems to be a lot of confusion over exactly which type of OLEDs are currently out there in the market.

    There are two OLED `generations':

    1) Small molecule - these use small organic molecules (think anthracene). They require pretty much conventional vacuum-systems for preparation and hence are expensive. However, they are emissive (unlike LCDs). These are the OLEDs we start to see in cameras etc. Lifetimes are pretty good.

    2) Polymer - this is the 2nd gen - here the manufacturing is all roll-to-roll or inkjet printing. These are going to be the el-cheapo reasonably-nice displays of the future. However, the lifetimes here are a concern - we're talking 15,000 hrs for the best blue polymers which isn't good enough yet.